For a beginner, which one would you guys recommend?I don't have much experience with landscapes, and I donīt know if an 18mm make that much difference to a 17mm.I'm also planning in going to France in December, so this lens would be used to take lots of photos around Paris.

Another question: features like IS make so much difference? I never had a lens without it.

For a beginner, which one would you guys recommend?I don't have much experience with landscapes, and I donīt know if an 18mm make that much difference to a 17mm.I'm also planning in going to France in December, so this lens would be used to take lots of photos around Paris.

Another question: features like IS make so much difference? I never had a lens without it.

Thanks!

I can comment on the sigma 17-50mm. A few months ago I bought a Sigma SD1M with 3 lenses - one being the 17-50mm. The problem I had with it was that the right hand 15-20% of the frame was always out of focus. At F11 it would start to correct itself. My Sigma dealer replaced it for me & the second one had similar problems. Whether it was the lens, or the camera's autofocus I don't know - but I gave up on it & my dealer exchanged it this time for a DP1M.

It is a pity because where the lens was good - it was excellent. But the crappy focus plane made it completely unreliable with many shots I had taken with it being unuseable.

When I first had n APS-C DSLR like the 50D I chose the 17-40 Canon. It works really well on that format and makes a great 'always on' lens. It's main downside is that it's physically a big lens.The Canon 10-22 has great reputation though and will certainly allow you to go a lot wider, it's probably the lens I'd choose now for that format.

The best thing is to try the lenses and see which you like the feel of and view from.

IS isn't so important on wide angles and is so rare on that sort of range anyway you won't have much choice.

When I first had n APS-C DSLR like the 50D I chose the 17-40 Canon. It works really well on that format and makes a great 'always on' lens. It's main downside is that it's physically a big lens.The Canon 10-22 has great reputation though and will certainly allow you to go a lot wider, it's probably the lens I'd choose now for that format.

I also had an APS-C Canon (20D) long ago along with a 10-22 and 16-35. I really liked both lenses quite a bit. The build quality on the 16-35 was clearly more rugged and it was a little smoother operating, but it was also heavier by quite a bit. Seeing that you also have the 28-135, the 10-22 makes the most sense to me. You can't go wrong with the 10-22 or the 17-40 Canons.

APS-C are cameras with smaller sensor. Most affordable DSLRs have smaller sensors, typically around 24x16 mm while "full format" sensor is 24x36. The sensor used to be very expensive, so using smaller sensors is a way of keeping cost down.

Now, Canon, Nikon and Sony have cameras with full frame sensors (24x36 mm) but those cameras still cost 2000-3000$US (or so).

Lenses made for small sensors will not work on a full frame camera, but full frame lenses are larger and more expensive.

The 17-40 lives on my camera most of the time. It's not perfect, but it is a tank. I'm very hard on my equipment, and my camera goes anywhere I go. The AF control cable somehow got severed a few years ago, but mechanically and optically, it's still going strong. I can't say that about my former non-L lenses.

Personally I don't think the Canon 17-40mm f4 makes much sense on an APS-C body. It was designed as a full frame wide angle lens and for APS-C there are several 17/18-50mm f2.8's to choose from (I had the Tamron 17-50mm f2.8 and I thought that it was excellent) or several lenses in the 10-20mm type range.

Years ago I had a Canon 10-22mm but personally I wouldn't recommend that lens. I found that it had some vignetting and distortion and I replaced mine with a Sigma 12-24mm which although not as wide (every mm makes a difference at the wide end) is a much superior lens IMVHO with zero vignetting or distortion.

And YES, IS is a lovely thing. You can get a 17/18-50mm f2.8 with IS but sadly for Canon users you will not get a lens in the 10-20mm range with IS.

Personally I don't think the Canon 17-40mm f4 makes much sense on an APS-C body. It was designed as a full frame wide angle lens and for APS-C there are several 17/18-50mm f2.8's to choose from (I had the Tamron 17-50mm f2.8 and I thought that it was excellent) or several lenses in the 10-20mm type range.

Years ago I had a Canon 10-22mm but personally I wouldn't recommend that lens. I found that it had some vignetting and distortion and I replaced mine with a Sigma 12-24mm which although not as wide (every mm makes a difference at the wide end) is a much superior lens IMVHO with zero vignetting or distortion.

And YES, IS is a lovely thing. You can get a 17/18-50mm f2.8 with IS but sadly for Canon users you will not get a lens in the 10-20mm range with IS.

I think you're absolutely correct considering only optics. The 17-40 has the advantage in build, especially when being used as a primary field lens.

I think that most if not all lenses have adequate built these days. My Tamron 17-50mm f2.8 never felt like it would fall apart and when I sold it (for a very good price) the buyer sent me a message saying how pleased he was with it and that he "could sell it as new" which I think says good things about its build as after years of use there wasn't a mark on it.

As for the 17-40mm being a good field lens, if you mean weather sealing then you'd have to remember to fit a filter and have a weather sealed body too

Bottom line:1 - I wan't a lens that I can shoot landscapes and also use for shotting weeding and garduations.2 - For shooting weedings, I believe I need a bright lens (Aperture of f/2.8 or less (2.0, 1.8, etc.))3 - I wan't a lens that I can use in my Canon 50D, but that will also fit in a Fullframe (that I will buy next year).